Table 2.

Clinical effects of Nigella sativa supplementation on the nervous system

Study design	Population	Part of the herb, dose, and duration of treatment	Result	References
Double-blinded crossover clinical trial	23 epileptic children	Water extract of black seed (40 mg/kg/8 h), 10 weeks	Significant reduction of mean frequency of seizures	[80]
Pilot, double-blinded crossover clinical trial	22 epileptic children	Thymoquinone (1 mg/kg), 10 weeks	Significant reduction of frequency of seizures	[81]
Prospective, randomized, single-blinded, controlled, crossover pilot study	30 intractable epileptic patients	40 – 80 mg/kg/day of black seed oil, 10 weeks	No beneficial effects in the frequency and severity of seizures	[82]
Placebo-controlled clinical trial	40 healthy elderly volunteers	500 mg NS seed capsule twice a day, 9 weeks	Improvement of cognition, memory, and attention	[83]
Placebo-controlled clinical trial	48 healthy adolescent males	500 mg NS capsule once daily, 4 weeks	Enhancements of mood, anxiety, and cognition	[84]
-	35 male opiate addicts	500 mg NS daily, 12 weeks	Significant reduction of withdrawal effects	[85]
Randomized, triple-blind, active, and placebo-controlled clinical trial	52 women with cyclic mastalgia	Topical 600 mg NS oil twice a day, 2 months	Significant improvement of the pain scores	[86]

NS, Nigella sativa.